Hi guys, i'm sorry to revive this thread, but i've got a really annoying problem with my new soundcard ( ASUS Xonar STX ) on my new gentoo installation...
I use this card only with headphones and in windows works flawlessly.
The system boot up correctly with the headphone selected, but every first time i try to use mpd through ncmpc ( after the reboot ) the card switch back from headphone to speaker ( and i can hear the "click" from the relay ).
So i need to switch to "headphones" through alsamixer before i can hear something from my headphones...
I've compiled the driver into the kernel and as module, but the problem still persists...
Have someone got this problem???

I can't say that I think my device is constantly switching between the two, but managing this problem is trivial with alsamixer installed. Here's what I do to manage headphone vs. speaker output: Create two files:

Now just run your headphones.sh file sometime during boot or as an Autostart script and voilà, output will always be redirected to your headphones at the prescribed volume. You can also add both commands to your path and "run" them quickly from a run prompt in X to switch the output back and forth between them when necessary.

Hello and sorry for another revival but I've encountered another issue. I've been a happy Xonar XTS user for about two months, but yesterday for some reason I started hearing mild crackling in left headphone during playback at higher volume levels. I tested it with different headphones and the problem persisted, however playback in windows is as good as before. On gentoo it occurs in every application I've tested so far, namely aplay, mpd, mplayer, firefox and steam.
I'm not sure if it has anything to do with this, but I noticed a silent noise when no sound is played, also when I do play some music I can hear it even when the Master control level is at 0%. The headphones impedance in alsamixer is set to < 64 ohms. Could it be that there is some detrimental gain being applied?